1. Field of the Invention
Aspects of the present invention relate to a cooling device, which cools an image development cartridge and laser scanning unit used in forming images on print media, and an image forming apparatus having the same installed therein.
2. Description of the Related Art
Photocopiers, printers, multifunction apparatuses and similar image forming apparatuses may be broadly divided into color image forming apparatuses and black-and-white image forming apparatuses. The advantages of black-and-white image forming apparatuses compared to other image forming apparatuses are that they are generally smaller and provide faster printing speeds.
Generally in black-and-white image forming apparatuses, the print medium (i.e., paper, transparency, etc.) is moved from the paper supply tray by the pick-up roller and follows a predetermined course past an organic photoconductive (OPC drum), on the surface of which the image is formed, and a transfer roller rotating while facing the Organic photoconductor. The image formed on the Organic photoconductor is transferred to the print medium as it passes between the transfer roller and the Organic photoconductor. The print medium, on which the image is printed, then passes through a fuser assembly, where the image is fused to the surface of the print medium by an application of high temperatures and pressures. The print medium is then either discharged from the main body of the image forming apparatus, or is sent back through the main body of the image forming apparatus, via a duplex printing path, so that printing on the other side of the printing medium may occur.
The fuser assembly comprises a heating roller maintained at a high temperature, and a pressure roller, which presses the heating roller with high pressure while rotating. A fuser assembly with this structure maintains a high temperature both in a printing mode thereof and a warming-up mode thereof, and, consequently, emits heat for a long period. As a result, other components in the image forming device, such as the Organic photoconductor and the laser scanning unit, also heat up due to the heat emitted by the fuser assembly.
The Organic photoconductor is installed in the development cartridge inside the printer housing, and comprises a photosensitive layer on a surface thereof, which is sensitive to heat. Therefore, in general, the Organic photoconductor is unable to maintain a constant temperature due to the heat which the Organic photoconductor itself produces during operation, and the heat generated by the fuser assembly. In this situation, normal printing quality cannot be ensured.
Furthermore, structural limitations resulting from the Organic photoconductor being installed on the inside of the development cartridge, surrounded by a charging member, a cleaning blade, and a developer roller, render natural cooling of the Organic photoconductor difficult.
Moreover, the laser scanning unit to scan the Organic photoconductor is usually installed on top of the image development part, which comprises the Organic photoconductor. Generally, the laser scanning unit comprises a light source, a polygonal mirror, a spindle motor and a plurality of optical members. It is important to isolate or reduce the heat generated from the fuser assembly, as a minute change in the location or dimensions of laser scanning units, caused by the rise in temperature, may have a significant effect on the precision of components used in scanning the Organic photoconductor.
Taking the above factors into consideration, development of an apparatus that effectively cools down the laser scanning unit and the image development part is acutely needed.